1. Technical Field of the Invention
The present invention relates to cellular communications networks and, in particular, to the network processing of subscriber service features in response to subscriber feature selection as well as to the determination of when features are implicated during call set up and delivery.
2. Description of Related Art
Existing cellular telephone networks offer their subscribers a number of special service features. Typically, these features are offered in addition to regular cellular telephone service, and thus access to and use of these features requires subscriber payment of an additional charge. Examples of these service features include voice mail, call forwarding, speed dialing, multi-leg calling, conference calls, call transfers, flexible alerting, and the like.
In the current (TR45) network reference model (NRM) for the wireless (cellular) telephone network, the home location register (HLR) is the primary network node responsible for the execution of such service features. A subscriber activates, deactivates or requests the execution of a service feature by dialing a feature code through their mobile station. A message including the dialed feature code is then sent by the mobile station over the air interface, through the base station (BS), and on to the serving mobile switching center (MSC). A feature request message is then sent by the mobile switching center to the home location register for evaluation. The home location register then returns a feature request return result message which includes instructions which specify the actions, if any, to be taken by the mobile switching center for responding to the feature code and implementing the requested service feature. A similar process relating to feature execution is implemented at the home location register in connection with the set up and delivery of an incoming call dialed to a subscriber mobile station.
Recent advances in network architecture have been made to implement a wireless intelligent network (IN) in connection with cellular telephone networks. The primary effect of intelligent network organization is to move the "intelligence" for directing operations provided by the network from its current location in each mobile switching center and perhaps other network nodes, to instead being located in one or more central nodes often referred to in the art as service control points (SCPs. It is anticipated that many if not all of the service features actuated either by subscriber dialed feature codes or in the context of a call set up and delivery will eventually be implemented by the service control point rather than the home location register. This raises network processing issues with respect to both feature dispatching (i.e., where has the service feature been implemented) following a subscriber request, and feature arbitration (i.e., the relative prioritization of the features implemented among various nodes) during call set up and delivery.